The model A1278 in front of me doesn't look like the above. It has 10 screws holding a single piece base onto the body, and not a single quick-release catch in sight. The battery bay looks different as well, but removing the HDD is just as easy.

That is because you are looking at a MacBook Pro A1278, not the MacBook Unibody. Apple made the regular MacBook in an aluminum enclosure in 2008 and the following aluminum model was changed to be called the MacBook Pro.